| Most people do not incorporate if they engage in securities trading from my experience that is! I am not sure what you would gain from either forming an LLC or a Corporation for that matter. Also, remember, forming a C corporation means that all gains or lossess would be treated as capital gains or losses to the corporation only, thus there would be no flow thru to your personal tax returns.
Furthermore, any gains generated from your business would be subject to corporation tax, and any distributions of these retained earnings would again be taxed to you on your tax return. Thus you would be subject to double taxation!!!
The LLC form of business would not be required generally, and I would urge you to contact your CPA or tax advisor to determine whether you my have some unique circumstances that would make it desirable for you to incorporate your trading of options business into an LLC! | 
